perf record: Split out counter creation into a helper function

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Documentation/perf_counter/builtin-record.c

@@ -336,20 +336,13 @@ static void synthesize_events(void)
 	closedir(proc);
 }
 
-static void open_counters(int cpu, pid_t pid)
+static int group_fd;
+
+static void create_counter(int counter, int cpu, pid_t pid)
 {
 	struct perf_counter_attr attr;
-	int counter, group_fd;
 	int track = 1;
 
-	if (pid > 0) {
-		pid_synthesize_comm_event(pid, 0);
-		pid_synthesize_mmap_events(pid);
-	}
-
-	group_fd = -1;
-	for (counter = 0; counter < nr_counters; counter++) {
-
 	memset(&attr, 0, sizeof(attr));
 	attr.config		= event_id[counter];
 	attr.sample_period	= event_count[counter];
@@ -358,10 +351,9 @@ static void open_counters(int cpu, pid_t pid)
 	attr.comm		= track;
 	attr.inherit	= (cpu < 0) && inherit;
 
-		track = 0; // only the first counter needs these
+	track = 0; /* only the first counter needs these */
 
-		fd[nr_cpu][counter] =
-			sys_perf_counter_open(&attr, pid, cpu, group_fd, 0);
+	fd[nr_cpu][counter] = sys_perf_counter_open(&attr, pid, cpu, group_fd, 0);
 
 	if (fd[nr_cpu][counter] < 0) {
 		int err = errno;
@@ -394,7 +386,21 @@ static void open_counters(int cpu, pid_t pid)
 		error("failed to mmap with %d (%s)\n", errno, strerror(errno));
 		exit(-1);
 	}
+}
+
+static void open_counters(int cpu, pid_t pid)
+{
+	int counter;
+
+	if (pid > 0) {
+		pid_synthesize_comm_event(pid, 0);
+		pid_synthesize_mmap_events(pid);
 	}
+
+	group_fd = -1;
+	for (counter = 0; counter < nr_counters; counter++)
+		create_counter(counter, cpu, pid);
+
 	nr_cpu++;
 }